Canary M-500 Monos- which 300B tube-

I have no experience with your Canary amp, but I am using the EML 300B XLS tubes in my SET 300B amp. To me, they were worth every penney.

You can spend more, but you can't go wrong with the XLS tubes.

There are several members that have, or have used, the Takatsuki, Royal Pricess, and the XLS tubes, and I'm sure their comments will follow.

I went from Chinese Mesh-Plates, which I thought were quite good, until the EML 300B XLS tubes took their place. No comparison.

Best of luck, regards,
Dan

Bopper,
I've used all three of the tubes you listed in my amplifier but have no experience with your Canary. The EML XLS and the Sophia RP are much superior to the EH 300b in my SET amplifier.The EH could be a better match in your particular push pull amplifier than it was with mine. The EH is also much less expensive and you'll need 4 pairs for your mono blocks.
Charles,

I use the EH 300B in my Canary Ref 2- with 8 pairs the economy had to be considered. I like them quite a bit. I have no experience with the other tubes you mention.

Good Listening

Peter